Using your smartphone’s GPS system, it will tell your Facebook friends (provided they have the feature turned on that you) are nearby. Rather than share your exact location, though, it will only show that you are in close proximity, say within half a mile. Then, if you want, you can manually share your exact location with a friend you’d like to meet up with, so they can see where you are located in a particular park, airport or city block.

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Your timeline may get a little more personal: Facebook announced it will roll out a location-based friend-finding feature on its mobile app.

The optional feature, called “Nearby Friends,” will launch on Thursday and allow users to see when their friends are located nearby. Users will only be able to effectively use the feature if two or more friends agree to share location information through Facebook.

“If you turn on Nearby Friends, you’ll occasionally be notified when friends are nearby, so you can get in touch with them and meet up,” writes Andrea Vaccari, product manager at Facebook in a blog. "For example, when you’re headed to the movies, Nearby Friends will let you know if friends are nearby so you can see the movie together or meet up afterward.”

Facebook wants to make it very clear that the service isn’t required, or even default – the headline of the blog post reads: “Introducing A New Optional Feature Called Nearby Friends.” In lieu of having the service on all the time, users can also share their precise location with friends for a set amount of time. Users can also choose what groups they want to share this information with, just like any other Facebook post.

The social media service suggests it can be used to organize meet-ups or offer recommendations to friends.

“When you see a friend visiting a place you’ve been, it’s the perfect opportunity to send a recommendation for a great restaurant,” writes Mr. Vaccari. “You can also make last-minute plans to meet up with a friend who happens to be in the same place you’re headed to.”

The service will not be available for users under 18, and at first will only be available for users in the United States. The roll out will be slow, only going to select users this week and slowly expanding from there, which is likely due to the potential privacy issues.

"Once you start bringing this to a mass audience, you need to be cautious," says Jules Polonetsky, director of the Future of Privacy Forum, to the AP. "So inadvertent oversharing is not possible."

This roll out comes on the heels of a surge in popularity of location-based social apps such as Tinder and retail app experimentation with location-based beacons. Already, location-based technology has gained acceptance: a 2013 Pew Research poll found 74 percent of people used location-based services on their phones.